We also took several of the shell-fishes, or testaceous animals, which are always found floating upon the water, particularly the Helix Janthina and Violacea; they are about the size of a snail, and are supported upon the surface of the water by a small cluster of bubbles, which are filled with air and consist of a tenaceous slimy substance that will not easily part with its contents; the animal is oviparous, and these bubbles serve also as a nidus for its eggs. It is probable that it never goes down to the bottom, nor willingly approaches any shore; for the shell is exceedingly brittle, and that of few fresh water snails is so thin: every shell contains about a tea-spoonful of liquor, which it easily discharges upon being touched, and which is of the most beautiful red purple that can be conceived. It dies linen cloth, and it may perhaps be worth enquiry, as the shell is certainly found in the Mediterranean, whether it be not the Purpura of the ancients.

On the 8th, in latitude 8° 25’ North, longitude 22° 4’ West, we found a current setting to the southward, which the next day in latitude 7° 58’ longitude 22° 13’ shifted to the N.N.W. ¾ W. at the rate of one mile and a furlong an hour. The variation here, by the mean of several azimuths, appeared to be 8° 39’ West.